tools: Get only verbose output with V=1
Fix having verbose build with V=0, e.g:
make V=0 -C tools/ perf
Signed-off-by: Robert Richter <robert.richter@calxeda.com>
Link: http://lkml.kernel.org/r/20130503134953.GU8356@rric.localhost
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>